<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>demo05</title>
</head>
<body>
        <script>
                var i = 26;
                function fn1() {        
                  var i = 24;
                  function fn2() {      
                    function fn3() {    
                      console.log(i);
                    }
                    fn3();
                  }
                  fn2();
                }
                fn1();
              </script>
              <p><a href="第四章.html">返回上一级</a></p>
</body>
</html>